1. Technical Field of the Invention
The embodiments of the invention relate to wireless communication systems and, more particularly, to analog-to-digital converters used in such wireless communication systems.
2. Description of Related Art
Communication systems are known to support wireless and wire lined communications between wireless and/or wire lined communication devices. Such communication systems range from national and/or international cellular telephone systems to the Internet to point-to-point in-home wireless networks. Generally, each type of communication system is constructed, and hence operates, in accordance with one or more communication standards. For instance, wireless communication systems may operate in accordance with one or more standards including, but not limited to, IEEE 802.11, Bluetooth, advanced mobile phone services (AMPS), digital AMPS, global system for mobile communications (GSM), code division multiple access (CDMA), local multi-point distribution systems (LMDS), multi-channel-multi-point distribution systems (MMDS), and/or variations thereof.
Depending on the type of wireless communication system, a wireless communication device, such as a cellular telephone, two-way radio, personal digital assistant (PDA), personal computer (PC), laptop computer, home entertainment equipment, etc., communicates directly or indirectly with other wireless communication device(s). For direct communications (also known as point-to-point communications), the participating wireless communication devices tune their receivers and transmitters to the same channel or channels (e.g., one of the plurality of radio frequency (RF) carriers of the wireless communication system) and communicate over that channel(s). For indirect wireless communications, each wireless communication device communicates directly with an associated base station (e.g., for cellular services) and/or an associated access point (e.g., for an in-home or in-building wireless network) via an assigned channel. To complete a communication connection between the wireless communication devices, the associated base stations and/or associated access points communicate with each other directly, via a system controller, via the public switch telephone network, via the Internet, and/or via some other wide area network.
For a wireless communication device to participate in wireless communications, it generally includes a built-in radio transceiver (i.e., receiver and transmitter) or is coupled to an associated radio transceiver (e.g., a station for in-home and/or in-building wireless communication networks, RF modem, etc.). As is known, the transmitter may include a data modulation stage, one or more intermediate frequency (IF) stages, and a power amplifier. The data modulation stage converts raw data into baseband signals in accordance with a particular wireless communication standard. The one or more intermediate frequency stages mix the baseband signals with one or more local oscillator signal(s) to produce RF signals. The power amplifier amplifies the RF signals prior to transmission via an antenna.
As is also known, the receiver is coupled to the antenna and may include a low noise amplifier, one or more intermediate frequency stages, a filtering stage, and a data recovery stage. The low noise amplifier receives inbound RF signals via the antenna and amplifies the signal. The one or more intermediate frequency stages mix the amplified RF signals with one or more local oscillator signal(s) to convert the amplified RF signal into baseband signals or IF signals. The filtering stage filters the baseband or IF signals to attenuate frequencies outside of the bandwidth of the filter to produce filtered signals. The data recovery stage recovers raw data from the filtered signals in accordance with the particular wireless communication standard employed.
Generally, in many wireless devices that operate from a battery, power consumption is a significant concern. Accordingly, employing various techniques to reduce power consumption in the operation of the device may extend its battery life. For example, low supply voltage chips may be utilized in the wireless device. Another method is to allow the display to become inactive after a time out period, if no user activity is noted. Still another technique is to place a processor in a sleep or suspend mode if activity is absent for a specified time period.
Accordingly, a need exists to continually find further techniques to reduce power consumption in a wireless device.